Try removing the space between Start and ($tag); and make sure that $tag has something in it.

I found it hard to really follow your question though. You might want to just include the whole block of code that is troublesome and you may get a better answer

Best of luck

$_.=($=+(6<<1));print(chr(my$a=$_));$^H=$_+$_;$_=$^H;
print chr($_-39); # Easy but its ok.
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